Bring required travel documents for the countries you're visiting, as well as identification for re-entry to the U.S. Passports are required for re-entry to the U.S. by air. Visit the Department of State's website for destination information.
U.S. Passport or other recommended ID for U.S. citizens (Carry it; do not pack it). Visit the U.S. Department of State: Travel website for more information on passports.
Green Card (Form I-551) or document for Lawful Permanent Residents (Advance Parole if LPR status is pending). Visit the U.S Citizenship and Immigration Services website for more on green cards. Failure to have Form I-551 or document for lawful permanent residents could result in a $545 waiver fee.
Notarized travel permission letters for minors traveling without their parents; Entry documentation for the country or countries you will be visiting. (Is a visa required?) Visit the U.S. Department of State: Travel website for more information.
Declare everything you are bringing in from abroad, even if you bought it in a duty-free shop. This merchandise is also subject to U.S. duty fees and other restrictions. It will be easier to fill out the CBP declaration if you have an envelope with receipts from all of your purchases.
If you are traveling with a lot of new jewelry, be sure to have the appraisals or receipts.
Be cautious when buying something from a street vendor. Keep in mind that the merchandise may be counterfeit and/or unsafe and you may have to surrender it to U.S. Customs and Border Protection when you get home.
Know that things bought abroad for personal use or as gifts are eligible for duty exemptions. If you are bringing them back for resale, they're not.
Know the difference between prohibited merchandise (such as ivory, tortoise shell products, absinthe, and counterfeit items) and restricted merchandise.
Be aware that many foreign made medications are not FDA-approved, and you cannot bring them into the U.S. Also, when traveling abroad, bring only the amount of medication you'll need during the trip in its original container.
Don't bring any food into the U.S. without first checking to see if it is permitted. Also, any and all live birds and bird products, whether for personal or commercial use, may be restricted and/or quarantined.
You should have permits and/or certificates if you're bringing restricted animal and plant commodities regulated by the U.S. Department of Agriculture, Animal and Plant Health Inspection Service: USDA APHIS Permits.
Understand that CBP officers can inspect you and your belongings without a warrant. This may include your luggage, vehicle, and personal searches and is meant to enforce our laws as well as protect legitimate travelers.
If you are traveling with your pet, you must bring Proof of Rabies vaccinations for a dog. This is recommended but not required for cats. Check for requirements regarding other pets: USDA APHIS: Pet Travel.
Register your items prior to your travel.
Bring receipts or registration paperwork. Use CBP Form 4457 for firearms and for any new electronics, such as a camera or laptop that you're taking with you. (Only suggested if traveling with recently purchased goods. Not necessary for goods more than 6 months old.) You might have to pay duty on these items if you have not registered your item or cannot prove you owned it prior to your departure.
If you have more questions, visit the CBP Info Center to ask a question and find an answer.